More specifically, the invention relates to a control valve assembly having a low-pressure side suitable for connection with a vacuum pump or the like and a high-pressure side suitable for connection with a supply container containing a pressure medium, both pressure sides comprising a closable inlet connecting piece, the junction conduit thereof being in flow connection with a guage.
In many technical branches, for example refrigeration engineering, it is necessary to transfer pressure media in containers, whereby the latter are previously to be evacuated. Refrigerators and, in particular, motor car air-conditioning systems, for instance, require for the initial starting or after repair of the system a charging of a cooling mixture, as a rule in the form of a liquified gas, in the circulation of the apparatus, for which this circulation has first to be evacuated.
In order that such process can be carried out in small workshops or even on the road, it is necessary for the mechanic concerned to be able to use a control valve assembly that permits the precise observation of this relatively dangerous transferring process.
Accordingly, a control valve assembly of the previously mentioned kind is available on the market, the armature casing thereof being divided into a low-pressure side for evacuating the system to be charged, and a high-pressure side for charging the system with gas. Here, the hand wheels of the shut-off valves on the system side are to be found in each case on the interface, and the hand wheels of the shut-off valves of the pump side or supply-container side are to be found on the front side of the armature casing.
The main disadvantages of these control valve assemblies is that the progress of flow in the assembly cannot be sufficiently supervised and, in particular, that there is no possibility of determining whether the flow routes or the medium being transferred are free from impurities. Moreover, the positioning of the hand wheels on the sides is less than satisfactory for easy manipulation.